Forget about the BBC's all-singing, all-dancing, all-vote counting television set, Eddie Mair and Carolyn Quinn want to show you around the studios from where BBC Radio 4's election coverage will be broadcast. A tour of the studios didn't quite go as planned, however, as the pair – enjoying a little fun at the expense of their TV colleagues – dissolved into hysterical laughter. Hear for yourself here, Quinn corpsing after about one minute, then virtually hyperventilating after three minutes. Four minutes in, and they've both lost it. "Is it the word bank?" asks Mair. An edited version will be played out on PM tonight.